 /*
  * Copyright (C) 2005, 2006 db4objects Inc. (http://www.db4o.com) and others.
  *
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * db4objects - Initial API and implementation
  * Boris Bokowski (IBM Corporation) - bug 118429
  */
 package org.eclipse.core.internal.databinding.validation;

 import org.eclipse.core.databinding.validation.IValidator;
 import org.eclipse.core.databinding.validation.ValidationStatus;
 import org.eclipse.core.internal.databinding.BindingMessages;
 import org.eclipse.core.runtime.IStatus;

 /**
  * ReadOnlyValidator. A validator that can be used as a partial validator for read-only fields.
  */
 public class ReadOnlyValidator implements IValidator {

     private static ReadOnlyValidator singleton = null;

     /**
      * Returns the ReadOnlyValidator
      *
      * @return the ReadOnlyValidator
      */
     public static ReadOnlyValidator getDefault() {
         if (singleton == null) {
             singleton = new ReadOnlyValidator();
         }
         return singleton;
     }

     public IStatus validate(Object value) {
         // No changes are allowed
 return ValidationStatus.error(BindingMessages
                 .getString("Validate_NoChangeAllowedHelp")); //$NON-NLS-1$
 }

 }

